firefox@esr

Install command: 
brew install --cask firefox@esr

Names: Mozilla Firefox ESR, Mozilla Firefox Extended Support Release

Web browser

https://www.mozilla.org/en-US/firefox/all/#product-desktop-esr

Development: Pull requests

Cask JSON API: /api/cask/firefox@esr.json

Cask code: firefox@esr.rb on GitHub

Current version: 140.7.0

Requirements: macOS >= 10.15

Conflicts with casks:

firefox 147.0.2 Web browser Mozilla Firefox
firefox@beta 148.0b10 Web browser Mozilla Firefox Beta
firefox@cn 116.0 Chinese version of Firefox firefox-cn

Analytics:

Installs (30 days)
firefox@esr 170
Installs (90 days)
firefox@esr 433
Installs (365 days)
firefox@esr 1,560